ENERGY DISSIPATION BEHAVIOURS AND SEISMIC REDUCTION PERFORMANCE OF A PROPOSED VELOCITY AND DISPLACEMENT DEPENDENT HYDRAULIC DAMPER (VDHD)

Abstract

A new oil‐pressure Velocity and Displacement Dependent Hydraulic Damper (VDHD) is proposed by adding an additional Relief Valve parallel to the Throttle Valve with a different aperture size. This objective is to obtain an adaptive control by changing the damping coefficient of the VDHD for better control of structural movement during earthquake. In order to simulate its actual energy elimination, a mathematical analysis model is developed based on the Maxwell Model, which is modified by adding a serial friction model and a small damper parallel to the friction model in this study. The mathematical simulated results are compared with the actual energy‐dissipating behaviours of this proposed damper. The comparison shows that this proposed mathematical modelling could accurately simulate the relation of force and displacement as well as the relation of force and velocity during the process of energy dissipation. In addition, results of both the laboratory shaking table test and simulation analyses are used to test and verify the seismic reduction performance of this proposed damper. The experimental and simulation results show that in spite of the magnitude of the earthquake, the proposed VDHD device has a superior effect on the control of structural displacement by achieving effective acceleration reduction. Santrauka Siūlomas naujas hidraulinis i greiti ir poslinki reaguojantis slopintuvas (HGPS), sukurtas prie droselinio vožtuvo su kintama apertūra pridejus atbulini vožtuva. Buvo siekiama užtikrinti geresne adaptyvia konstrukcijos judejimo žemes drebejimo metu kontrole keičiant HGPS slopinimo koeficienta. Norint modeliuoti tikraji energijos pašalinima, buvo sukurtas matematinis modelis, pagristas Maksvelo modeliu. Šis modelis buvo pakeistas prie trinties modelio pridejus nuosekluji trinties modeli ir nedideli slopintuva. Matematinio modeliavimo rezultatai lyginami su tikraja siūlomo gesintuvo energijos sklaida. Palyginimas rodo, kad matematinio modeliavimo rezultatai atitinka tikraja siūlomo gesintuvo elgsena. Lyginant skaičiavimo rezultatus su eksperimentiniais matyti, kad siūlomas matematinis modeliavimas leidžia tiksliai išreikšti jegos ir poslinkio bei jegos ir greičio ryšius, susidarančius energijos sklaidos metu. Laboratoriniai rezultatai, gauti naudojant vibracini stala, ir modeliavimo rezultatai taikomi tirti bei tikrinti siūlomo gesintuvo itaka mažinant seismines konstrukcijos charakteristikas. Eksperimentiniai ir modeliavimo rezultatai rodo, kad nepaisant žemes drebejimo laipsnio, siūlomas gesintuvas labai pagerina konstrukcijos poslinkiu kontrole efektyviai mažindamas judejimo pagreiti.